Answer
In general, mistimed apoptosis would result if the signal inducing it was perceived or seemed to be perceived at the wrong time. This could result either from mistimed-release of the signal or, more likely, defective proteins early in the process of apoptosis (especially receptors) which were stuck in always-- or too frequently --"on" mode due to a mutation.
Work Step by Step
This highlights the importance of having all parts of signal transduction working properly. A defective receptor could lead to overactivity and problems resulting from that.